If you've ever tried to press flowers or leaves between pieces of paper, you know that each specimen takes lots of painstaking work. Can you imagine collecting and preserving 150,000 plants, flowers, and leaves? That's exactly what Ynes Mexia did. Mexia was a Mexican-American botanist, but she was also a non-traditional college student, a creative field scientist, and an explorer.

She didn't get started with science until age 51

Mexia lived in many places throughout her life. She was born in 1870, most likely in Washington DC, where her father was a Mexican diplomat. The family moved often, and Mexia lived in Texas, Pennsylvania, Canada, and Mexico before settling in San Francisco in 1908. She moved to California after divorcing her second husband, Agustin de Reygados; her first husband, Herman de Laue, died in 1898.

While living in San Francisco, Mexia went on hikes with the Sierra Club, which brought her peace after the divorce. She became so interested in botany and science that she started taking classes at UC Berkley in 1921 at the age of 51. She was what we would now call a non-traditional student, taking classes alongside college students 30 years her junior. Though she took many classes over the course of 16 years, she never completed a degree in science.

She was an adaptable field scientist

During Mexia's impressive career as a natural scientist, she encountered some speed bumps - many of which were the 20th century version of obstacles that modern field scientists experience today. After completing a sampling expedition, she needed a way to get her samples back to California. Instead of dropping them off at the post office, she had to send them to the California Academy of Sciences on a steamship and hope they would make it. She traveled across Nevada, Utah, and Arizona in an open Model T Ford, not a van with four-wheel drive. Her fieldwork took her to remote locations, requiring days or even weeks of travel. On one trip, she traveled up the Amazon River by steamship, canoe, and balsa raft just to reach her site.

Mexia's work made its mark on botany, with specimens she collected now housed in museums across the US and Europe. Almost 100 years after her botany career began, her research is still "integral" to the classification of plants in North America and beyond.

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